To foster sustainability pursuits, regulation by state-imposed legislation is often crucial, but self-regulation by corporations, associations, and other non-state actors increasingly exerts pressures and provides incentives for sustainable practices. In order to shed more light on the complex interplay among sustainability regulations and self-regulation, this study focused on a highly regulated field: the German wine industry. Using a social network analysis, this study identified the most central actors (e.g., associations, regulatory institutions) that need to be addressed in order to ensure the enforcement of sustainability. By analyzing 15 semi-structured interviews with the key actors, we outlined their understanding of sustainability, and classified three distinctive governance patterns. These mixed methods and in-depth analyses revealed that self-regulation by associations plays a crucial role in terms of enhancing sustainability, but regulation remains an important trigger in this context. This article concludes with some lessons for regulation and self-regulation policies that can ensure sustainability within an organizational field.